3.5.7.23 -stable review patch. If anyone has any objections, please let me know.
------------------ From: Anatol Pomozov <anatol.pomo...@gmail.com> commit f3cff25f05f2ac29b2ee355e611b0657482f6f1d upstream. 'samples' is 64bit operant, but do_div() second parameter is 32. do_div silently truncates high 32 bits and calculated result is invalid. In case if low 32bit of 'samples' are zeros then do_div() produces kernel crash. Signed-off-by: Anatol Pomozov <anatol.pomo...@gmail.com> Acked-by: Tejun Heo <t...@kernel.org> Signed-off-by: Jens Axboe <ax...@kernel.dk> Cc: Jonghwan Choi <jhbird.c...@gmail.com> Signed-off-by: Luis Henriques <luis.henriq...@canonical.com> --- block/cfq-iosched.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/block/cfq-iosched.c b/block/cfq-iosched.c index fb52df9..4d27120 100644 --- a/block/cfq-iosched.c +++ b/block/cfq-iosched.c @@ -1484,7 +1484,7 @@ static u64 cfqg_prfill_avg_queue_size(struct seq_file *sf, if (samples) { v = blkg_stat_read(&cfqg->stats.avg_queue_size_sum); - do_div(v, samples); + v = div64_u64(v, samples); } __blkg_prfill_u64(sf, pd, v); return 0; -- 1.8.3.2 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/